Tab structure, battery cell and battery
By designing the gradually increasing subset fluid and partition gap in the polar ear structure, the problem of insufficient coverage area and thickness during stacking and forming of the all-pole ear structure is solved, and reliable welding of the inner layer of the battery is achieved and sharp edges and corners are prevented. risk.
Patent Information
- Application Number
- CN202420673034.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-02
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2034-04-02
AI Technical Summary
When the existing all-pole ear structure is stacked and formed, due to the small current collector sheet structure, the outer ear length is limited, the coverage area is small, the welding plane is thin, and it is difficult to weld, and the inner ear cannot be effectively welded.
Design the pole ear structure, in which the pole sheet is equipped with a plurality of subsets of fluids gradually increasing along the length direction, and covers it to the axis position of the electric core through winding operation, ensuring the thickness and welding effect of the all-pole ear structure, using incline or step The stacking position of the subset of the shape of the subset of the fluid and the partition gap are adjusted to achieve stable molding of the all-pole ear.
Effectively improve the coverage area and thickness of the all-pole ear structure, ensuring the reliability of welding, especially in large cylindrical batteries, the inner layer of the ear is welded, avoiding the reduction in thickness and the risk of sharp edges and corners caused by hollowing .
Smart Images
Figure CN222338450U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of battery tab structures, in particular to a tab structure, a battery core and a battery. Background Art
[0002] In the battery structure, the tab is a metal conductor that leads the positive and negative electrodes in the battery cell. It is the contact point between the positive and negative electrodes of the battery during charging and discharging. The tab structure includes single-pole tab and full-pole tab.
[0003] Among them, the full-pole tab is a tab that can make surface contact with the positive and negative current collectors, and is connected to the battery housing or current collector plate through the full area of the current collector to form a stable full-pole tab conductive structure. The full-pole tab structure can effectively increase the flow conduction area and overcurrent capacity of the battery, and help reduce the internal resistance and heat generation of the battery.
[0004] The full-ear structure is formed by flattening or stacking. During stacking, multiple small current collectors need to be stacked at the ends of the battery cell. The existing small current collectors are generally multiple equal-sized sheet structures. As the battery cell is wound, the length of the ear on the outer circle is limited, and the area it covers is small. The welding plane after the ear is flattened is thin and difficult to weld. In addition, the cross-section in the thickness direction of the overall plane is a rectangle, and the inner ear cannot be effectively welded. Utility Model Content
[0005] In order to solve at least the above technical problems existing in the prior art, the embodiments of the present utility model provide a tab structure, a battery cell and a battery.
[0006] One aspect of an embodiment of the utility model provides a pole ear structure, including a pole piece and a current collector; the pole piece has a set length, and the current collector is arranged on the long side of the pole piece; the current collector includes a plurality of sub-current collectors, and along the length direction of the pole piece, the heights of the plurality of sub-current collectors gradually increase.
[0007] In some embodiments, the sub-current collector is used to be superimposed on the side end of the battery cell formed by the pole piece; the end of each sub-current collector coincides with the axis of the battery cell.
[0008] In some embodiments, the end of the sub-current collector is horizontal and arranged parallel to the long side of the pole piece.
[0009] In some embodiments, the end of the sub-current collector is inclined and has a set angle with the extension line of the long side of the pole piece.
[0010] In some embodiments, the corners of the fluid subset are chamfered.
[0011] In some embodiments, adjacent subset current collectors include separation gaps, and the separation gaps have a set angle with the long side of the pole piece, and the set angle is less than 90°.
[0012] In some embodiments, a separation gap is provided between adjacent subset current collectors, and the separation gap is arranged perpendicular to the extension line of the long side of the pole piece.
[0013] On the other hand, an embodiment of the present invention further provides a battery cell, comprising the above-mentioned tab structure.
[0014] Another aspect of the embodiments of the present invention further provides a battery, comprising the above-mentioned tab structure or the above-mentioned battery cell.
[0015] The pole ear structure, battery cell and battery provided by the embodiments of the utility model have different lengths of subset current collectors. When the pole piece is wound, the short end of the subset current collector is wound first. As the pole piece is continuously wound, the diameter of the battery cell gradually increases, and the short subset current collector is close to the axis of the battery cell, while the long subset current collector is relatively far from the axis. During the stacking and forming operation, after the pole ears are stacked, the outer pole ears can be stacked layer by layer to the axis of the battery cell to ensure the thickness of the entire pole ear structure, thereby effectively ensuring the welding effect and realizing the welding of the inner layer of the large cylindrical battery and the pole ears. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] By reading the detailed description below with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, wherein:
[0017] In the drawings, the same or corresponding reference numerals represent the same or corresponding parts.
[0018] Figure 1 The structure of the pole piece and the current collector in the pole ear structure provided by the embodiment of the utility model is shown in FIG. Figure 1 ;
[0019] Figure 2 The structure of the pole piece and the current collector in the pole ear structure provided by the embodiment of the utility model is shown in FIG. Figure 2 .
[0020] In the figure:
[0021] 10: pole piece; 20: current collector;
[0022] 21: Sub-fluid; 22: Separation gap. DETAILED DESCRIPTION
[0023] In order to make the purpose, features and advantages of the utility model more obvious and easy to understand, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.
[0024] An embodiment of the utility model provides a pole ear structure, including a pole piece and a current collector. By changing the structure of the current collector, when a full pole ear structure is realized, both the pole ear located on the inner side of the battery cell and the pole ear located on the outer side of the battery cell have a certain coverage area, and can cover to a set position after stacking to meet the full pole ear design requirements.
[0025] The following is a detailed description of the tab structure, the various structures of the battery cell and the battery, and the positional relationship and connection relationship between the various structures provided in the embodiments of the present invention in conjunction with the accompanying drawings.
[0026] like Figure 1 and Figure 2 As shown, the electrode sheet 10 has a set length, and a current collector 20 is arranged on the long side of the electrode sheet 10. When the battery cell is formed, the battery cell includes a positive electrode sheet 10, a negative electrode sheet 10 and a separator, and the separator is used to separate the positive electrode sheet 10 and the negative electrode sheet 10, and the three are wound into a cylindrical battery cell, wherein the positive electrode sheet 10 and the negative electrode sheet 10 both include a current collector 20, and after the battery cell is wound, the current collector 20 is located at the side end of the battery cell.
[0027] In a stacked full-tab battery cell, if the shapes of the various sub-current collectors 21 are the same, as the winding diameter of the battery cell gradually increases, the ends of the sub-current collectors 21 located on the outside will gradually move away from the axial position of the battery cell after being folded, thereby failing to ensure the thickness of the middle part of the full-tab structure.
[0028] In the embodiment of the utility model, the current collector 20 includes a plurality of sub-current collectors 21, and the heights of the plurality of sub-current collectors 21 gradually increase along the length direction of the pole piece 10. As the height of the sub-current collector 21 increases, the area (length) covered by the sub-current collector 21 in the stacked full-electrode-ear battery cell is larger. For example, the sub-current collector 21 is used to be superimposed on the side end of the battery cell formed by the pole piece 10; the end of each sub-current collector 21 coincides with the axis of the battery cell.
[0029] When the pole piece 10 is wound, the pole piece 10 at the short end of the sub-current collector 21 is connected to the winding needle. The sub-current collector 21 at this position is close to the axis of the battery cell. As the pole piece 10 is wound, the sub-current collector 21 on the newly wound pole piece 10 is relatively far away from the axis of the battery cell. Therefore, the height of the sub-current collector 21 at this position is relatively increased accordingly. After stacking, it can still cover the axis of the battery cell.
[0030] For example, in the embodiment of the present invention, the end of the sub-current collector 21 is horizontal and arranged parallel to the long side of the pole piece 10. When the heights of the plurality of sub-current collectors 21 gradually increase, the heights of the plurality of sub-current collectors 21 are stepped, or the end of the sub-current collector 21 is inclined and has a set angle with the extension line of the long side of the pole piece 10. Under this structure, the plurality of sub-current collectors 21 are continuously inclined as a whole.
[0031] In the embodiment of the present invention, the shape of the end of the sub-current collector 21 is not limited thereto, and can also be other shapes as long as the heights of the plurality of sub-current collectors 21 gradually increase. For example, the shape of the end of the sub-current collector 21 can be determined according to the diameter and shape of the battery cell.
[0032] When the battery cell is wound, as the diameter increases, the height of the subset current collector 21 located on the outside also increases accordingly, thereby ensuring that the end of the subset current collector 21 can cover the axial position of the battery cell. At this time, the subset current collector 21 is fully covered at the axial position of the battery cell, ensuring the thickness of the full ear structure.
[0033] For example, in an embodiment of the present invention, the corners of the subset current collector 21 are chamfered, and the chamfering prevents the end of the pole ear from being too sharp, which has a protective effect on the battery shell or the structure connected to the pole ear to avoid / reduce the probability of scratches. For example, the battery is packaged in a soft package material to avoid / reduce the probability of the pole ear puncturing the packaging. In addition, it also avoids / reduces the impact of sharp corners on adjacent stacked subset current collectors 21.
[0034] In the embodiment of the utility model, the adjacent sub-current collectors 21 include a separation gap 22, and the separation gap 22 has a set angle with the long side of the pole piece 10, that is, the separation gap 22 is set obliquely, or the separation gap 22 is set perpendicularly to the extension line of the long side of the pole piece 10. By changing the angle of the separation gap 22, the stacking position of the sub-current collectors 21 can be partially adjusted, and the forming state of the full-electrode ear structure can be further adjusted. For example, the angle of the separation gap 22 can be determined according to the diameter and shape of the battery cell.
[0035] The utility model also provides a battery cell, including the above-mentioned tab structure. And also provides a battery, including the above-mentioned tab structure or the above-mentioned battery cell. The tab structure has a certain thickness, especially the center position of the full tab structure, to avoid the situation where the thickness is reduced due to hollowing, and to ensure the reliability of welding when the battery is formed; especially when forming a large cylindrical battery, the tab inside the cut and stacked large cylindrical full tab battery can be welded in the inner layer.
[0036] The pole ear structure, battery cell and battery provided by the embodiments of the utility model have different lengths of the subset current collectors 21. When the pole piece 10 is wound, the short end of the subset current collector 21 is wound first. As the pole piece 10 is continuously wound, the diameter of the battery cell gradually increases, and the short subset current collector 21 is close to the axis of the battery cell, while the long subset current collector 21 is relatively far from the axis. During the stacking operation, after the pole ears are stacked, the outer pole ears can be stacked layer by layer to the axis of the battery cell to ensure the thickness of the entire pole ear structure, thereby effectively ensuring the welding effect and realizing the welding of the inner layer of the large cylindrical battery and the pole ears.
[0037] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.
[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0039] The above are only specific implementations of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.
Claims
1. A tab structure, characterized in that: It comprises a pole piece (10) and a current collector (20); The pole piece (10) has a set length, and the current collector (20) is arranged on the long side of the pole piece (10); The current collector (20) comprises a plurality of sub-current collectors (21), and along the length direction of the pole piece (10), the heights of the plurality of sub-current collectors (21) gradually increase.
2. The tab structure according to claim 1, characterized in that: The sub-current collector (21) is used to be superimposed on the side end of the battery core formed by the pole piece (10); The end of each of the sub-current collectors (21) coincides with the axis of the battery core.
3. The tab structure according to claim 2, characterized in that: The end of the sub-current collector (21) is horizontal and is arranged parallel to the long side of the pole piece (10).
4. The tab structure according to claim 2, characterized in that: The end of the sub-current collector (21) is inclined and has a set angle with the extension line of the long side of the pole piece (10).
5. The tab structure according to claim 2, characterized in that: The corners of the sub-fluid collector (21) are chamfered.
6. The tab structure according to claim 2, characterized in that: Adjacent sub-current collectors (21) include separation gaps (22), and the separation gaps (22) have a set angle with the long side of the pole piece (10), and the set angle is less than 90°.
7. The tab structure according to claim 2, characterized in that: A separation gap (22) is provided between adjacent sub-current collectors (21), and the separation gap (22) is arranged perpendicular to the extension line of the long side of the pole piece (10).
8. A battery cell, characterized in that: The invention comprises the electrode ear structure according to any one of claims 1 to 7.
9. A battery, characterized in that: The invention comprises the tab structure according to any one of claims 1 to 7 or the battery cell according to claim 8.